| 摘要 |
<p>PURPOSE:To reduce the radiation loss generated within the duration from the time of heating-up to the time of service by a method wherein the proper capacity of a heating element is calculated based upon the heat quantity of remaining hot water so as to heat up the water in a hot water storage tank by energizing for the entire period of midnight power supply time. CONSTITUTION:When the temperature of the water in the hot water storage tank 1 is uniformized to T2 deg.C by being circulated with a circulating pump 6 after some amount of the hot water is removed for use from the hot water storage tank with a total volume of Vl full of the hot water having the temperature of T1 deg.C and then the same amount of the water having the temperature of t deg.C is replenished to the tank 1, the heat quantity C kcal of remaining hot water, the heat quantity Cin kcal to heat the water in the hot water storage tank for heating-up and the required capacity of the heating element Wkw are obtained in case of the rated heating-up temperature of T deg.C from the relationships as follows: C=V(T2-t), Cin=V(T-t)-C, W=Cin/860. The heating element 8 is energized for the entire period of midnight power supply time so as to heat up the water in the hot water storage tank simultaneously with the expiration of midnight power supply time.</p> |
